The present disclosure relates to a color mixer for producing a colored beam of light, for example, in a theatrical lighting fixture. In theater, stage, and other entertainment production applications, it is often desirable to project a colored light beam. Initially, this was accomplished by using colored glass, followed by colored gelatin. The current term “gel” refers generally to theatrical lighting color filters and is derived from this past use of gelatin as a color-filtering medium. Sheets of dyed polyester (called “gels”) are now standard within the industry for lighting color filter applications.
It is also desirable to be able to project more than one color from a single lighting fixture. Rotating color wheels provided multiple colors, however, such color wheels proved to be too large, and too limited in the number of colors available.
A further desirable feature is the ability to produce a colored light beam of varying hues. For example, it may be desirable to project a light beam at a stage in colors ranging from white light to a very deep shade of blue, symbolizing a transition from day to night. Gel strings accomplish this transition by comprising an assembly of numerous individual frames of color attached together to create a gel having a color gradient ranging from clear to a deep hue of a particular color, such as blue in the previous example.
Gel strings may be used in combination with a motor drive system to remotely position the desired color in front of a light source. Such motor drive systems are referred to as color scrollers and are commercially available, such as the Smart Color® line of scrollers from Apollo Design Technology, Inc. of Fort Wayne, Ind. However, color scrollers are limited to the number of individual frames that can be coupled together, thus limiting the color gradient. The highest number of frames available on color scrollers is presently 32. Designers of theatrical programs frequently need more colors than the limited palette offered by current products.